Image forming apparatus and image forming method

ABSTRACT

An image forming apparatus includes a correction unit configured to execute first correction processing to be executed to bring reproduction characteristics of an image formed by an image forming unit close to a target value and second correction processing different from the first correction processing, and an adjustment unit configured to execute a plurality of adjustment processing including the second correction processing, wherein correction processing by the correction unit is set to be executed at a predetermined timing, and wherein in a case that correction processing by the correction unit is executed at the set timing after adjustment processing is executed by the adjustment unit, the image forming apparatus performs control not to execute the second correction processing included in the adjustment processing and to execute the second correction processing after executing the first correction processing by the correction unit.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/626,684, filed Feb. 19, 2015, which claims the benefit of JapanesePatent Application No. 2014-032210, filed Feb. 21, 2014, and JapanesePatent Application No. 2014-149938, filed Jul. 23, 2014, all of whichare hereby incorporated by reference herein in their entirety.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to an image forming apparatus whichperforms control to optimize adjustment processing performed within theapparatus according to an execution reservation of calibration.

Description of the Related Art

Some of recent electrophotographic method image forming apparatuses areequipped with an internal adjustment function executed at startup. Theinternal adjustment function is to automatically execute “cleaning ofeach unit in the apparatus”, “adjustment processing”, “in-apparatusdensity adjustment” for stabilizing output, and the like immediatelyafter startup of the image forming apparatus. One example of thein-apparatus density adjustment is a correction unit using a patch imageformed on an intermediate transfer member. The patch image is read by asensor disposed near the intermediate transfer member, and a measurementresult is reflected in various image formation conditions, such as avoltage condition and laser power, so that a maximum density and ahalftone characteristic can be corrected.

The in-apparatus density adjustment is performed other occasion than thestartup of the apparatus in some cases. Output characteristics of theelectrophotographic method image forming apparatus varies according to adegree of use of the image forming unit or a change in an ambientenvironment. Thus, the in-apparatus density adjustment is automaticallyexecuted every certain number of outputs, so that an image quality canbe kept at a certain level without troubling a user.

In addition, many image forming apparatuses are equipped with an“on-paper density adjustment” function for further stabilizing output oftheir own. The on-paper density adjustment is to read a patch imageformed on a sheet by a predetermined measurement unit and reflect a readresult in the above-described image formation conditions. Since theoutput characteristics of the image forming apparatus when actuallyforming an image on a sheet is reflected, when compared to thepreviously described in-apparatus density adjustment, outputstabilization can be realized more accurately in response to a useenvironment of a user and a sheet type.

Generally, when a user instructs execution of calibration by himself orherself for stabilization of image quality, both of the on-paper densityadjustment and the in-apparatus density adjustment are often performedin turn. First, the on-paper density adjustment is performed, andcorrection is performed using a measurement result of the outputcharacteristics when an image is formed on a sheet. Then, afterperforming the on-paper density adjustment, the in-apparatus densityadjustment is performed. This process is performed for creating a targetvalue for the in-apparatus density adjustment to be performed everycertain number of subsequent outputs.

A user who requires a certain level of accuracy for image outputinstructs execution of calibration by himself or herself when startingup the image forming apparatus. At that time, same processing isoverlapped in the in-apparatus density adjustment included in theinternal adjustment function to be executed immediately after thestartup of the apparatus and in the in-apparatus density adjustmentincluded in the calibration processing to be then executed in responseto the instruction of the user. The overlap of the processing causesproblems of not only generation of an unnecessary wait time from thestartup of the apparatus to the completion of the calibration but alsoprogression of toner consumption and wear and tear of the image formingunit.

As a method for solving the problems, a method is discussed for avoidingoverlap of calibration execution instructions (see Japanese PatentApplication Laid-Open No. 2006-212918). In Japanese Patent ApplicationLaid-Open No. 2006-212918, a method is discussed which performs control,when instructions to execute same type calibration are overlappinglyissued, not to execute the calibration latterly instructed.

However, according to the above-described conventional technique, if auser issues an instruction to execute calibration immediately after thestartup of the image forming apparatus and during execution of theinternal adjustment processing, the in-apparatus density adjustmentincluded in the internal adjustment processing is performed. Then, whenthe calibration instructed by the user is executed, the in-apparatusdensity adjustment included in a series of the processing is notperformed. In other words, the in-apparatus density adjustment using ameasurement result of the output characteristics when an image isactually formed on a sheet is not performed. Therefore, an originalimage stabilization effect cannot be achieved in some cases in theabove-described in-apparatus density adjustment to be performed everycertain number of outputs.

Thus, the present invention is directed to realization of an imageforming apparatus which can reduce a wait time and consumption ofconsumable products while maintaining an image quality to which ameasurement result of the output characteristics when an image isactually formed on a sheet is reflected.

SUMMARY OF THE INVENTION

According to an aspect of the present invention, an image formingapparatus includes a correction unit configured to execute firstcorrection processing to be executed to bring reproductioncharacteristics of an image formed by an image forming unit close to atarget value and second correction processing different from the firstcorrection processing and an adjustment unit configured to execute aplurality of adjustment processing including the second correctionprocessing, wherein correction processing by the correction unit is setto be executed at a predetermined timing, and wherein in a case thatcorrection processing by the correction unit is executed at the settiming after adjustment processing is executed by the adjustment unit,the image forming apparatus performs control not to execute the secondcorrection processing included in the adjustment processing and toexecute the second correction processing after executing the firstcorrection processing by the correction unit.

Further features of the present invention will become apparent from thefollowing description of exemplary embodiments with reference to theattached drawings.

According to the present invention, the image forming apparatus canreduce a wait time necessary for execution of calibration andconsumption of the consumable products while maintaining an imagequality to which a measurement result of the output characteristics whenan image is actually formed on a sheet is reflected.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating an entire configuration of animage forming system.

FIG. 2 is a cross section of a printer 111.

FIG. 3 illustrates a processing flow of internal adjustment processingaccording to a first exemplary embodiment and a second exemplaryembodiment.

FIG. 4 is a flowchart illustrating the internal adjustment processingaccording to the first exemplary embodiment.

FIG. 5 is a flowchart illustrating reset processing of the internaladjustment processing according to the first exemplary embodiment.

FIG. 6 is an example of an information table A 600 of the internaladjustment processing according to the first exemplary embodiment andthe second exemplary embodiment.

FIG. 7 is an example of a reset table A 700 of the internal adjustmentprocessing according to the first exemplary embodiment.

FIG. 8 is a flowchart illustrating the internal adjustment processingaccording to the second exemplary embodiment, a third exemplaryembodiment, and a fourth exemplary embodiment.

FIG. 9 is an example of an information table B 900 of the internaladjustment processing according to the exemplary embodiments of thepresent invention.

FIGS. 10A to 10D are examples of a user interface (UI) screen regardingto a calibration function according to the exemplary embodiments of thepresent invention.

FIG. 11 illustrates relationship among sheet information, an imageforming mode, and a calibration execution mode according to the thirdexemplary embodiment and the fourth exemplary embodiment.

FIG. 12 illustrates a processing flow of the internal adjustmentprocessing according to the third exemplary embodiment and the fourthexemplary embodiment.

FIG. 13 is a flowchart illustrating the internal adjustment processingaccording to the third exemplary embodiment.

FIG. 14 is a flowchart illustrating the reset processing of the internaladjustment processing according to the third exemplary embodiment.

FIG. 15 is an example of an information table C 1500 of the internaladjustment processing according to the third exemplary embodiment andthe fourth exemplary embodiment.

FIG. 16 is an example of a reset table B 1600 of the internal adjustmentprocessing according to the third exemplary embodiment.

FIG. 17 is an example of an information table D 1700 of the internaladjustment processing according to the third exemplary embodiment.

FIG. 18 is an example of a reset table C 1800 of the internal adjustmentprocessing according to the fourth exemplary embodiment.

FIG. 19 is an example of an information table E 1900 of the internaladjustment processing according to the fourth exemplary embodiment.

DESCRIPTION OF THE EMBODIMENTS

Various exemplary embodiments, features, and aspects of the presentinvention will be described in detail below with reference to thedrawings.

FIG. 1 is a block diagram illustrating an entire configuration of animage forming system according to exemplary embodiments of the presentinvention. The image forming system includes an image forming apparatus101 and an information processing apparatus 100. The informationprocessing apparatus 100 and the image forming apparatus 101 areconnected to a local area network (LAN) 102 so as to communicate witheach other. The image forming apparatus 101 may be a multi-functionperipheral (MFP) or a single function peripheral (SFP). The imageforming apparatus 101 includes an image control unit 103, a scanner 109,a printer 111, and an operation unit 113. The image control unit 103controls the scanner 109, the printer 111, and the operation unit 113.

A central processing unit (CPU) 104 reads a control program stored in aread-only memory (ROM) 105 to execute various control processingincluding printing control or the like. A random access memory (RAM) 106is used as a temporary storage area, such as a main memory and a workarea, of the CPU 104. A scanner interface (I/F) 108 connects the scanner109 to the image control unit 103. Image data of a document read by thescanner 109 is transmitted to the image control unit 103 via the scannerI/F 108 and used for printing, storage, transfer, or the like. A printerI/F 110 connects the printer 111 to the image control unit 103. Imagedata to be printed by the printer 111 is transmitted from the imagecontrol unit 103 to the printer 111 via the printer I/F 110 and printedon a sheet by the printer 111. An operation unit I/F 112 connects theoperation unit 113 to the image control unit 103. The operation unit 113may have various configurations, such as a unit only including a switchor a light emitting diode (LED) and a unit including a touch panel typeliquid crystal display (LCD) unit. Information input via the operationunit 113 is transmitted to the CPU 104 via the operation unit I/F 112,subjected to necessary processing by the CPU 104, and displayed on adisplay unit 114 included in the operation unit 113. A network I/F 107connects the image control unit 103 to the LAN 102. The network I/F 107receives print data and various information pieces from the informationprocessing apparatus 100 on the LAN 102.

Next, operations of the printer 111 in the electrophotographic methodimage forming apparatus 101 are described with reference to FIG. 2. Theprinter 111 forms an electrostatic latent image by exposure light turnedon based on an exposure time converted by the image control unit 103 anddevelops the electrostatic latent image to form a single color tonerimage. Then, the printer 111 overlaps the single color toner images witheach other to form a multicolor toner image, transfers the multicolortoner image to a sheet 11, and fixes the multicolor toner image on thesheet 11.

The printer 111 includes a sheet feeding unit, photosensitive members22Y to 22K, injection chargers 23Y to 23K, toner cartridges 25Y to 25K,development devices 26Y to 26K, an intermediate transfer member 27, atransfer roller 28, a cleaning means 29, and a fixing unit 30. The sheetfeeding unit includes a sheet feeding tray 21 and a manual feeding tray,not illustrated, on which the sheets 11 are stacked. The printer 111 mayinclude a plurality of sheet feeding trays to load different types andsizes of sheets on each tray.

The above-mentioned photosensitive drums (photosensitive members) 22Y to22K have a configuration in which an organic photoconductive layer isapplied on an outer circumference of an aluminum cylinder, and a drivingforce is transmitted from a driving motor, not illustrated, to thephotosensitive drums to rotate. The driving motor rotates thephotosensitive drums 22Y to 22K in a counterclockwise direction inresponse to an image forming operation.

Four injection chargers 23Y to 23K for charging the photosensitivemembers of yellow (Y), magenta (M), cyan (C), and black (K) are providedfor each station as primary charging means, and the injection chargersrespectively include sleeves 23YS to 23KS.

Exposure light to the photosensitive drums 22Y to 22K is transmittedfrom scanner units 24Y to 24K, and surfaces of the photosensitive drums22Y to 22K are selectively exposed to the light, so that anelectrostatic latent image is formed.

Four development devices 26Y to 26K for developing yellow (Y), magenta(M), cyan (C), and black (K) toners to visualize the electrostaticlatent image are provided for each station as development means, and thedevelopment devices respectively includes sleeves 26YS to 26KS. Eachdevelopment device is detachably mounted.

The intermediate transfer member 27 contacts the photosensitive drums22Y to 22K and rotates in a clockwise direction in association with therotation of the photosensitive drums 22Y to 22K when an image is formed,so that a single color toner image is transferred thereto. Then, atransfer roller 28 is brought into contact with the intermediatetransfer member 27 to hold the sheet 11 therebetween and convey thesheet 11, and the multicolor toner image on the intermediate transfermember 27 is transferred to the sheet 11.

The fixing unit 30 which conveys the sheet 11 and melts and fixes thetransferred multicolor toner image to the sheet 11 includes a fixingroller 31 to heat the sheet 11 and a pressure roller 32 to press andcontact the sheet 11 to the fixing roller 31. The fixing roller 31 andthe pressure roller 32 have a hollow structure and respectively includeheaters 33 and 34 inside of them. In other words, the sheet 11 on whicha multicolor toner image is formed is conveyed, heated, and pressed bythe fixing roller 31 and the pressure roller 32, so that toner is fixedon the sheet surface.

The sheet 11 after fixing of the toner image is then discharged by adischarge roller 37 to a discharge tray 36, and the image formingoperation is completed. The cleaning means 29 removes toner remaining onthe intermediate transfer member 27, and waste toner remaining aftertransferring the four color toner image formed on the intermediatetransfer member 27 to the sheet 11 is collected to a cleaner container.

A density sensor 41 is disposed toward the intermediate transfer member27 to detect density of a toner patch formed on the surface of theintermediate transfer member 27. The CPU 104 reflects the measurementvalue to a calibration table for correcting density and gradationcharacteristics in the image control unit 103 and each image formationcondition on the image forming unit to execute in-apparatus densityadjustment processing.

A color sensor 42 is disposed toward an image forming surface of thesheet 11 on downstream of the fixing unit 30 to detect a red-green-blue(RGB) output value of a color of a mixed color patch which is formed andfixed on the sheet 11. The color sensor 42 is disposed within the colorimage forming apparatus 101, so that the detection can be automaticallyperformed before a sheet after fixing of an image is discharged to thedischarge unit. According to a first exemplary embodiment, the densitysensor 41 and the color sensor 42 are described as examples ofmeasurement means of a patch image, the measurement means are notlimited to them. For example, a configuration which measures a spectralreflectance of a patch image using a spectral colorimeter to performvarious image quality correction processing may be employed.

Next, internal adjustment processing to be performed immediately afterthe startup of the image forming apparatus 101 is described below.

When a power source of a printer is changed from off to on, the CPU 104controls the image forming apparatus 101 to perform the internaladjustment processing. If the CPU 104 detects that a user turns on apower source switch, not illustrated, of the image forming apparatus101, or a startup time preliminarily reserved has come, the CPU 104turns on the power source of the printer 111.

FIG. 3 illustrates a processing flow of the internal adjustmentprocessing according to the first exemplary embodiment. According to thepresent exemplary embodiment, the internal adjustment processingincludes five types of processing, i.e. processing A to the processingE, as illustrated in FIG. 3. According to the present exemplaryembodiment, the number of processing in the internal adjustmentprocessing are five for simplifying the description, however the numberof processing may be larger or smaller than five in actual processing.

The internal adjustment processing includes processing which is notperformed in calibration to be executed by an instruction from a user.For example, cleaning of the image forming units, such as theintermediate transfer member 27 and the photosensitive drums 22Y to 22K,and temperature control of the fixing unit 30 fall within the relevantprocessing. On the other hand, the internal adjustment processingincludes processing which is performed during the execution ofcalibration. For example, the in-apparatus density adjustment processingfalls within the relevant processing. Further, adjustment processing,such as refreshment processing of the development device and potentialcontrol of an image forming process, which needs to be performed priorto the in-apparatus density adjustment falls within the internaladjustment processing. As described above, the internal adjustmentprocessing for adjusting parameters related to image formation includesa plurality of processing including the in-apparatus density adjustment,and when the internal adjustment processing is executed, a series of theplurality of processing is performed.

Similarly, calibration also adjusts parameters related to imageformation and includes a plurality of processing including on-paperdensity adjustment the in-apparatus density adjustment. When thecalibration is executed, a series of the plurality of processing isperformed.

According to the present exemplary embodiment, the image formingapparatus 101 stores an information table A 600 of the internaladjustment processing in the ROM 105. The information table A 600records an execution order of processing included in the internaladjustment processing and whether each processing is interruptibleduring the execution. The information table A 600 further recordswhether each processing included in the internal adjustment processingoverlaps with processing to be performed when calibration is executed.The CPU 104 refers to the information table A 600 and control theexecution of the internal adjustment processing. FIG. 6 is an example ofthe information table A 600 of the internal adjustment processingaccording to the present exemplary embodiment. In the information tableA 600, the processing A, B, and D do not overlap with processing to beperformed when calibration is executed. Whereas the processing C and Eoverlap with the processing to be performed when calibration isexecuted.

Next, how calibration is performed according to the present exemplaryembodiment is described using an example of a user interface (UI) screenillustrated in FIGS. 10A to 10C.

The CPU 104 receives a predetermined operation by a user and displays acalibration instruction screen 1000 as illustrated in FIG. 10A on thedisplay unit 114. When a user presses an “execute” button 1001, the CPU104 receives a calibration execution instruction.

When the calibration execution instruction is received from the user,the CPU 104 controls the printer 111 to start calibration.

When calibration is executed, a plurality of processing is performed,and at least the on-paper density adjustment is included in theprocessing. When the on-paper density adjustment is executed, the CPU104 reflects a measurement result of a patch image fixed onto the sheet11 measured by the color sensor 42 to the calibration table and each ofthe image formation conditions. Accordingly, the on-paper densityadjustment is executed, and a correction table is created for bringingreproduction characteristics of an image formed by the image formingapparatus 101 close to a target value.

A part of the processing to be performed when calibration is executedoverlaps with the processing executed in the internal adjustmentprocessing. For example, the adjustment processing, such as refreshmentprocessing of the development device and potential control of the imageforming process, which needs to be performed prior to the in-apparatusdensity adjustment and the in-apparatus density adjustment fall withinthe relevant processing. The in-apparatus density adjustment is tocreate the correction table so as to bring the reproductioncharacteristics of an image formed by the image forming apparatus 101close to the target value similar to the on-paper density adjustment,however, a specific method are different. More specifically, forexample, a patch image formed on the intermediate transfer member 27 isread by the density sensor 41 disposed near the intermediate transfermember 27, and the measurement result is reflected to voltage conditionsand laser power. Accordingly, the maximum density and the halftonecharacteristic are corrected.

The CPU 104 performs the on-paper density adjustment function to reflectthe measurement result of the output characteristics when an image isformed on a sheet to the image formation conditions and then performsthe in-apparatus density adjustment.

Accordingly, the in-apparatus density adjustment can be performed basedon the result of the on-paper density adjustment, and accuracy ofcorrection is improved.

When a calibration execution instruction is received during execution ofthe internal adjustment processing, the CPU 104 controls the printer 111to automatically start execution of calibration immediately aftercompletion of the internal adjustment processing, in other words, withina predetermined time period.

Next, the internal adjustment processing when a calibration executioninstruction is received during execution of the internal adjustmentprocessing according to the present exemplary embodiment is describedwith reference to a flowchart in FIG. 4. Processing in the presentflowchart is realized by the CPU 104 of the image forming apparatus 101executing the processing according to a program stored in the ROM 105.

First, in step S401, the CPU 104 receives a calibration executioninstruction from a user. Next, in step S402, the CPU 104 determineswhether the printer has started the internal adjustment processing. Instep S402, if it is determined that the internal adjustment processinghas not been started (NO in step S402), the processing proceeds to stepS410, and the CPU 104 executes calibration and completes the processing.

Whereas, in step S402, if it is determined that the internal adjustmentprocessing has been started (YES in step S402), the processing proceedsto step S403. The CPU 104 determines whether the processing beingexecuted is stoppable with reference to the information table A 600 ofthe internal adjustment processing. In step S403, if it is determinedthat the processing being executed is not stoppable (NO in step S403),the processing proceeds to step S404. Then, the CPU 104 completes theprocessing being executed as it is and advances the processing to stepS407.

Whereas, in step S403, if it is determined that the processing beingexecuted is stoppable (YES in step S403), the processing proceeds tostep S405. In step S405, the CPU 104 determines whether the relevantprocessing overlaps with the processing to be performed when calibrationis executed which is instructed to be executed in step S401 withreference to the information table A 600 of the internal adjustmentprocessing. In step S405, if it is determined that the processing doesnot overlap with the processing to be performed when calibration isexecuted (NO in step S405), the processing proceeds to step S404. Then,the CPU 104 completes the processing being executed and advances theprocessing to step S407.

Whereas, in step S405, if it is determined that the processing overlapswith the processing to be performed when calibration is executed (YES instep S405), the processing proceeds to step S406. The CPU 104 stops theprocessing being executed and advances the processing to step S407.Next, in step S407, the CPU 104 interrupts the internal adjustmentprocessing. In step S408, the CPU 104 performs reset processing of theinternal adjustment processing.

FIG. 5 is a flowchart illustrating the reset processing of the internaladjustment processing. Processing in the present flowchart is realizedby the CPU 104 of the image forming apparatus 101 executing theprocessing according to a program stored in the ROM 105.

First, in step S501, the CPU 104 reads the information table A 600 ofthe internal adjustment processing from the ROM 105.

In step S502, the CPU 104 determines first processing scheduled to befirst executed in unperformed processing as a target of determinationprocessing in step S503.

In step S503, the CPU 104 refers to the information table A 600 of theinternal adjustment processing to determine whether the relevantprocessing overlaps with the processing to be performed when calibrationis executed.

If it is determined that the relevant processing does not overlap withthe processing to be performed when calibration is executed (NO in stepS503), the processing proceeds to step S504. In step S504, the CPU 104reads a reset table A 700 shown in FIG. 7 from the ROM 105, records therelevant processing as an execution target of the internal adjustmentprocessing, and then advances the processing to step S505. The resettable A 700 includes at least information about each processing to beperformed after restart of the internal adjustment processing and anexecution order of the processing.

Whereas if it is determined that the relevant processing overlaps withthe processing to be performed when calibration is executed (YES in stepS503), the processing proceeds to step S505.

In step S505, the CPU 104 determines whether overlap determinationprocessing in step S503 has been performed on all of the unperformedprocessing.

If it is determined that the determination processing has not beenfinished on all processing (NO in step S505), the CPU 104 returns theprocessing to step S502 and determines next processing in the executionorder in the information table A 600 as an execution target of thedetermination processing in step S503 to repeat the above-describedprocessing.

Whereas if it is determined that the determination processing has beenfinished on all processing (YES in step S505), the CPU 104 completes theprocessing in the present flowchart and returns the processing to stepS409 in FIG. 4.

Then, in step S409, the CPU 104 executes the rest of the internaladjustment processing according to the reset table A 700 of the internaladjustment processing. The CPU 104 initializes information in the resettable A 700 on the ROM 105 when completing the internal adjustmentprocessing.

When the internal adjustment processing is finished, the CPU 104executes calibration and completes the processing.

Specific processing which is performed when execution of calibration isinstructed during execution of the processing A is described below basedon the information table A 600 of the internal adjustment processing inFIG. 6.

In this case, the CPU 104 determines that the processing A is stoppablein step S403 and advances the processing to step S405. In step S405, theCPU 104 determines that the processing A does not overlap with theprocessing to be performed when calibration is executed, and completesexecution of the processing A in step S404.

Then, in step S407, the internal adjustment processing is interrupted,and in step S408, the reset processing of the internal adjustmentprocessing is performed, and as a result, the reset table A 700 shown inFIG. 7 is created. Each of the processing B and subsequent processingare subjected to determination of whether to overlap with the processingto be performed when calibration is executed, and the processing B andthe processing D, which are determined not to overlap, are determined assubsequent execution targets and executed.

As described above, according to the present exemplary embodiment, whenexecution of calibration is instructed during the execution of theinternal adjustment processing, processing which overlaps with theprocessing to be performed when calibration is executed is not performedin is in the internal adjustment processing. More specifically, ifcalibration is executed within a predetermined time period after theexecution of the internal adjustment processing, overlapping processingis performed not in the internal adjustment processing but in theexecution of the calibration.

In other words, after completion of the internal adjustment processing,both of the on-paper density adjustment and the in-apparatus densityadjustment are processed in turn as calibration. More specifically,processing included in the internal adjustment processing andcalibration instructed to be executed, namely adjustment processing suchas the in-apparatus density adjustment, refreshment processing of thedevelopment device, and potential control of the image forming processare cancelled. Further, these processing are performed after executionof the on-paper density adjustment. Thus, density adjustment isperformed based on the result of the on-paper density adjustment.

Therefore, the image forming apparatus can reduce a wait time andconsumption of consumable products without deteriorating an imagequality to which output characteristics obtained when an image isactually formed on a sheet by execution of calibration is reflected.

According to the above-described first exemplary embodiment, it isdescribed that calibration is instructed by a user after the imageforming apparatus 101 is started up, and the internal adjustmentprocessing is started. However, a method for instructing calibrationexecution is not limited the above-described one.

According to a second exemplary embodiment, a user can reserve executionof calibration at the startup of the image forming apparatus 101 inadvance, and a method for optimizing the internal adjustment processingis described.

An example of a calibration execution reservation method is describedwith reference to the UI screens in FIGS. 10A to 10D.

When the CPU 104 receives a predetermined operation by a user, the CPU104 displays the calibration execution instruction screen in FIG. 10A onthe display unit 114. When the user presses a “reservation setting”button 1002, the CPU 104 displays a calibration reservation settingscreen 1003 in FIG. 10B on the display unit 114. When the user presses a“YES” button 1004, the CPU 104 receives calibration executionreservation after startup of the image forming apparatus 101. Accordingto the present exemplary embodiment, the calibration executionreservation method is exemplified in the above-described method,however, a reservation method is not limited thereto.

For example, the CPU 104 may display a calibration reservation settingscreen 1005 in FIG. 10C on the display unit 114 when shutting down theimage forming apparatus 101. If a user presses a “YES” button 1006, theCPU 104 may control the image forming apparatus 101 to executecalibration when starting up next time.

In addition, reservation can be set in more detail by allowing a user tospecify date conditions including a day of week, date, and the like.Further, reservation can be set not from the operation unit 113 of theimage forming apparatus 101 but from an operation unit, not illustrated,installed in the information processing apparatus 100. Furthermore, theROM 105 may record an execution history of calibration, and the CPU 104may predict a trend of calibration execution after startup from theexecution history and automatically make the reservation. Thus, acalibration execution reservation can be set at a predetermined timing.

Next, an embodiment of the internal adjustment processing based onwhether the calibration execution reservation is made after startup ofthe image forming apparatus 101 is described with reference to aprocessing flowchart in FIG. 8. Processing in the present flowchart isrealized by the CPU 104 of the image forming apparatus 101 executing theprocessing according to a program stored in the ROM 105.

First, in step S801, the CPU 104 detects that the power source of theprinter 111 is turned on and advances the processing to step S802. Next,in step S802, the CPU 104 determines whether calibration execution afterstartup is reserved. In step S802, if it is determined that thecalibration is not reserved (NO in step S802), then in step S803, theCPU 104 performs control to execute the internal adjustment processingas indicated in the above-described information table A 600 and thencompletes the processing flow.

Whereas, in step S802, if it is determined that the calibration isreserved (YES in step S802), then in step S804, the CPU 104 executes theinternal adjustment processing according to information recorded in aninformation table B 900 shown in FIG. 9. The information table B 900 isstored in the ROM 105, and processing which does not overlap with theprocessing to be performed when calibration is executed is onlyregistered therein among the processing recorded in the informationtable A 600. In other words, if calibration is scheduled to be executedwithin a predetermined time period after execution of the internaladjustment processing, processing included in the internal adjustmentprocessing and in the calibration processing is not performed.

According to the present exemplary embodiment, processing registered inthe information table B 900 are only the processing A, the processing B,and the processing D, which are indicated in the information table A 600as “NO” about overlap with the processing to be performed whencalibration is executed. Therefore, in step S804, the CPU 104 executesthe internal adjustment processing in the order of the processing A, theprocessing B, and the processing D. Then, in step S805, the CPU 104executes calibration and completes the processing flow.

If calibration reserved by a user cannot be executed by some reasons,such as paper shortage, the CPU 104 may not execute optimizationprocessing of the internal adjustment processing in the above describedexemplary embodiment.

Accordingly, the present exemplary embodiment can avoid a situation inwhich originally required adjustment processing is not performed becausethe internal adjustment processing is performed by omittingpredetermined processing and then calibration is not executed.Therefore, the present exemplary embodiment can prevent printing frombeing executed in a state in which an appropriate image quality is notensured.

According to the present exemplary embodiment, optimization processingis automatically applied based on an advanced reservation state ofcalibration and after dealing with processing first performed inexecution of the internal adjustment processing. Therefore, in a systemin which calibration can be reserved in advance, a user can enjoy aneffect of the optimization processing without being conscious of it. Inother words, the in-apparatus density adjustment included in theinternal adjustment processing is cancelled, and the in-apparatusdensity adjustment is performed after execution of the on-paper densityadjustment. Thus, density adjustment is performed based on the result ofthe on-paper density adjustment.

Therefore, the image forming apparatus can reduce a wait time andconsumption of consumable products without deteriorating an imagequality to which output characteristics obtained when an image isactually formed on a sheet by execution of calibration is reflected.

According to a third exemplary embodiment, it is described the imageforming apparatus which can switch a plurality of image forming modes inresponse to information of a sheet to be used in printing. Switching ofthe image forming mode is to switch parameters related to an imageforming process, such as an image speed, transfer, and fixation. The CPU104 refers to, for example, grammage information of a sheet as shown inFIG. 11 to determine the image forming mode. In addition, the CPU 104may refer to other sheet information, such as a surface property, whichis not described in the following exemplary embodiment.

According to the present exemplary embodiment, the image formingapparatus 101 stores an information table C 1500 of the internaladjustment processing in the ROM 105. The information table C 1500includes information about an image forming mode targeted by eachprocessing included in the internal adjustment processing in addition tothe information recorded in the information table A 600 described in thefirst exemplary embodiment. The CPU 104 refers to the information tableC 1500 to control execution of the internal adjustment processing.

FIG. 12 illustrates a processing flow of the internal adjustmentprocessing in the image forming apparatus which has a plurality of imageforming modes. The internal adjustment processing includes both ofprocessing independent from the image forming mode and processingdependent on the image forming mode. Processing independent from theimage forming mode is executed only once by the CPU 104 as theprocessing A and the processing D in FIG. 12. On the other hand,processing dependent on the image forming mode is executed each for theimage forming modes 1 to 3 as the processing B, the processing C, andthe processing E in FIG. 12.

Next, calibration according to the present exemplary embodiment isdescribed. Image formation conditions are different among the pluralityof image forming modes, and difference occurs among image qualities oftheir print results. Thus, the image forming apparatus executescalibration in each of the plurality of image forming modes and canrealize a stable image quality regardless of sheet attributes. Forexample, as shown in FIG. 11, a calibration execution mode 1, acalibration execution mode 2, and a calibration execution mode 3 arerespectively prepared for the image forming mode 1, the image formingmode 2, and the image forming mode 3.

Next, a determination method of the calibration execution mode accordingto the present exemplary embodiment is described. When the CPU 104receives a predetermined operation by a user, the CPU 104 displays thecalibration execution instruction screen in FIG. 10A on the display unit114. When a user presses a “sheet setting” button 1009, the CPU 104displays a calibration sheet setting screen 1010 in FIG. 10D on thedisplay unit 114. In the calibration sheet setting screen 1010, sheetoption buttons 1011 to 1014 are displayed which are used for executionof calibration to form a patch image. If a user presses any of the sheetoption buttons 1011 to 1014 and then presses a determination button1015, the CPU 104 receives a calibration sheet setting. A case when a“thick paper” button 1013 is selected as a calibration sheet isdescribed below as an example.

With respect to each option of the calibration sheet, sheet attributeinformation, such as a grammage, is defined in advance. The CPU 104refers to both of the sheet attribute information and a relationshipbetween the sheet and the calibration execution mode indicated in FIG.11 to determine the calibration execution mode. According to the presentexemplary embodiment, a grammage of “thick paper” is defined as “230 g”.Therefore, as indicated in FIG. 11, the CPU 104 determines thecalibration execution mode as a “mode 2” targeting on a sheet having agrammage of 200 g to 250 g.

Next, the internal adjustment processing when a calibration executioninstruction is received during execution of the internal adjustmentprocessing according to the present exemplary embodiment is describedwith reference to a flowchart in FIG. 13. Processing in the presentflowchart is realized by the CPU 104 of the image forming apparatus 101executing the processing according to a program stored in the ROM 105.

First, in step S1301, the CPU 104 receives a calibration executioninstruction from a user. Then, in step S1302, the CPU 104 specifies thecalibration execution mode.

Next, in step S1303, the CPU 104 determines whether the printer hasstarted the internal adjustment processing. In step S1303, if it isdetermined that the internal adjustment processing has not been started(NO in step S1303), the processing proceeds to step S1313, and the CPU104 executes calibration and completes the processing.

Whereas, in step S1303, if it is determined that the internal adjustmentprocessing has been started (YES in step S1303), the processing proceedsto step S1304, and the CPU 104 determines whether the processing beingexecuted is stoppable with reference to the information table C 1500 ofthe internal adjustment processing. In step S1304, if it is determinedthat the processing being executed is not stoppable (NO in step S1304),the processing proceeds to step S1305. Then, the CPU 104 completes theprocessing being executed as it is and advances the processing to stepS1310.

Whereas, in step S1304, if it is determined that the processing beingexecuted is stoppable (YES in step S1304), the processing proceeds tostep S1306. In step S1306, the CPU 104 determined whether the relevantprocessing overlaps with the processing to be performed when calibrationis executed with reference to the information table C 1500 of theinternal adjustment processing. In step S1306, if it is determined thatthe relevant processing does not overlap with the processing to beperformed when calibration is executed (NO in step S1306), theprocessing proceeds to step S1305. Then, the CPU 104 completes theprocessing being executed and advances the processing to step S1310.

Whereas, in step S1306, if it is determined that the relevant processingoverlaps with the processing to be performed when calibration isexecuted (YES in step S1306), the processing proceeds to step S1307. Instep S1307, the CPU 104 determines whether the relevant processing isindependent from the image forming mode with reference to theinformation table C 1500 of the internal adjustment processing. In stepS1307, if it is determined that the relevant processing is independentfrom the image forming mode (YES in step S1307), the processing proceedsto step S1305. Then, the CPU 104 completes the processing being executedand advances the processing to step S1310.

Whereas, in step S1307, if it is determined that the relevant processingis not independent from the image forming mode (NO in step S1307), theprocessing proceeds to step S1308. In step S1308, the CPU 104 determineswhether the relevant processing targets on the image forming modeassociated with the calibration execution mode specified in step S1302with reference to the information table C 1500 of the internaladjustment processing. In step S1308, if it is determined that therelevant processing does not target on the image forming mode associatedwith the calibration execution mode (NO in step S1308), the processingproceeds to step S1305. Then, the CPU 104 completes the processing beingexecuted and advances the processing to step S1310.

Whereas, in step S1308, if it is determined that the relevant processingtargets on the image forming mode associated with the calibrationexecution mode (YES in step S1308), the processing proceeds to stepS1309. The CPU 104 stops the processing being executed and advances theprocessing to step S1310. In step S1310, the CPU 104 interrupts theinternal adjustment processing. Then, in step S1311, the CPU 104performs reset processing of the internal adjustment processing.

FIG. 14 is a flowchart illustrating the reset processing of the internaladjustment processing. Processing in the present flowchart is realizedby the CPU 104 of the image forming apparatus 101 executing theprocessing according to a program stored in the ROM 105.

First, in step S1401, the CPU 104 reads the information table C 1500 ofthe internal adjustment processing from the ROM 105.

In step S1402, the CPU 104 determines first processing scheduled to befirst executed in unperformed processing as a target of determinationprocessing in step S1403.

In step S1403, the CPU 104 refers to the information table C 1500 of theinternal adjustment processing to determine whether the relevantprocessing overlaps with the processing to be performed when calibrationis executed.

If it is determined that the relevant processing does not overlap withthe processing to be performed when calibration is executed (NO in stepS1403), the processing proceeds to step S1404. In step S1404, the CPU104 reads a reset table B 1600 shown in FIG. 16 from the ROM 105,records the relevant processing as an execution target of the internaladjustment processing, and then advances the processing to step S1407.The reset table B 1600 includes at least information about eachprocessing to be performed at the restart of the internal adjustmentprocessing and an execution order of the processing.

Whereas if it is determined that the relevant processing overlaps withthe processing to be performed when calibration is executed (YES in stepS1403), the processing proceeds to step S1405.

In step S1405, the CPU 104 determines whether the relevant processing isindependent from the image forming mode with reference to theinformation table C 1500 of the internal adjustment processing. In stepS1405, if it is determined that the relevant processing is independentfrom the image forming mode (YES in step S1405), the processing proceedsto step S1404. The processing in step S1404 is as described above. Then,the CPU 104 advances the processing to step S1407.

Whereas, in step S1405, if it is determined that the relevant processingis not independent from the image forming mode (NO in step S1405), theprocessing proceeds to step S1406. In step S1406, the CPU 104 determineswhether the relevant processing targets on the image forming modeassociated with the calibration execution mode specified in step S1302with reference to the information table C 1500 of the internaladjustment processing. In step S1406, if it is determined that therelevant processing does not target on the image forming mode associatedwith the calibration execution mode (NO in step S1406), the processingproceeds to step S1404. The processing in step S1404 is as describedabove. Then, the CPU 104 advances the processing to step S1407.

Whereas, in step S1406, if it is determined that the relevant processingtargets on the image forming mode associated with the calibrationexecution mode (YES in step S1406), the processing proceeds to stepS1407.

In step S1407, the CPU 104 determines whether overlap determinationprocessing in step S1403 has been performed on all of the unperformedprocessing.

If it is determined that the determination processing has not beenfinished on all processing (NO in step S1407), the CPU 104 returns theprocessing to step S1402 and determines next processing in the executionorder in the information table C 1500 as an execution target of thedetermination processing in step S1403 to repeat the above-describedprocessing.

Whereas if it is determined that the determination processing has beenfinished on all processing (YES in step S1407), the CPU 104 completesthe processing in the present flowchart and returns the processing tostep S1312 in FIG. 13.

Then, in step S1312, the CPU 104 executes the rest of the internaladjustment processing according to the reset table B 1600 of theinternal adjustment processing. The CPU 104 initializes information inthe reset table B 1600 on the ROM 105 when completing the internaladjustment processing.

When the internal adjustment processing is finished, the CPU 104executes calibration in step S1313 and completes the processing.

Specific processing which is performed when execution of calibrationusing “thick paper” is instructed during execution of the processing Ais described below based on the information table C 1500 of the internaladjustment processing in FIG. 15.

Description of the determination processing with respect to theprocessing A being executed is omitted since it is similar to that inthe first exemplary embodiment.

In step S1310, the internal adjustment processing is interrupted, and instep S1311, the reset processing of the internal adjustment processingis performed, and as a result, the reset table B 1600 shown in FIG. 16is created. As a result that the determination processing in stepsS1306, S1307, and S1308 are each performed on each of the processing Band subsequent processing, processing which overlaps with calibrationand targets on the image forming mode 2 is excluded, and processingother than that are set as subsequent execution targets.

Next, a method for optimizing the internal adjustment processing whenexecution of calibration at startup is reserved in the image formingapparatus having a plurality of image forming modes is described withreference to the processing flowchart in FIG. 8. Processing in thepresent flowchart is realized by the CPU 104 of the image formingapparatus 101 executing the processing according to a program stored inthe ROM 105.

The processing in step S801 is same as that in the second exemplaryembodiment, and the description thereof is omitted.

In step S802, the CPU 104 determines whether calibration execution afterstartup is reserved. In step S802, if it is determined that thecalibration is not reserved (NO in step S802), the CPU 104 performscontrol to execute the internal adjustment processing as indicated inthe above-described information table C 1500 and then complete theprocessing flow.

Whereas, in step S802, if it is determined that the calibration isreserved (YES in step S802), the CPU 104 executes the internaladjustment processing according to information recorded in aninformation table D 1700 shown in FIG. 17. The information table D 1700is recorded in the ROM 105 as many as the number of the calibrationexecution modes. A case when calibration using “thick paper”, namelycalibration in the calibration execution mode 2 is reserved is describedbelow as an example. Processing registered in the information table D1700 is processing indicated as “NO” about overlap with the processingto be performed when calibration is executed or processing of whichtarget image forming mode is other than “mode 2” among the processingrecorded in the information table C 1500. In other words, if calibrationin the mode 2 is scheduled to be executed within a predetermined timeperiod after execution of the internal adjustment processing, processingincluded in the internal adjustment processing and in the calibrationprocessing in the mode 2 is not performed.

In step S804, the CPU 104 executes the internal adjustment processing inthe order recorded in the information table D 1700. Then, in step S805,the CPU 104 executes calibration and completes the processing flow.

If calibration reserved by a user cannot be executed by some reasons,such as paper shortage, the CPU 104 may not execute optimizationprocessing of the internal adjustment processing in the above describedexemplary embodiment.

Accordingly, the present exemplary embodiment can avoid a situation inwhich originally required adjustment processing is not performed becausethe internal adjustment processing is performed by omittingpredetermined processing and then calibration is not executed.Therefore, the present exemplary embodiment can prevent printing frombeing executed in a state in which an appropriate image quality is notensured.

Further, if calibration reserved by a user cannot be executed, the CPU104 may execute the optimization processing of the above-describedinternal adjustment processing and then suspend printing in the imageforming mode associated with calibration. If a cause in preventingexecution of calibration is removed, and calibration is executed, thenthe CPU 104 restarts a suspended print job.

While the printing in the image forming mode associated with thereserved calibration is suspended, the CPU 104 precedently performsprinting in an image forming mode other than the relevant image formingmode.

Accordingly, printing can be prevented from being performed in a statein which an appropriate image quality is not ensured while maintainingan effect of the optimization of the internal adjustment processing. Inaddition, printing in the other image forming mode is precedent thereto,and a down-time of the apparatus can be reduced.

As described above, according to the present exemplary embodiment, theoptimization processing is applied to the image forming apparatus havinga plurality of image forming modes and calibration modes in response tothe calibration mode instructed to be executed. Accordingly, theoptimization processing can be performed by appropriately narrowing downthe target image forming mode.

Therefore, the image forming apparatus can reduce a wait time andconsumption of consumable products without deteriorating an imagequality in the image forming mode which is not the target ofcalibration.

According to the above-described third exemplary embodiment, anoptimization method of the internal adjustment processing is describedin the case that execution and reservation of a single mode calibrationis instructed. However, the optimization method is not limited to theabove-described one. Optimization of the internal adjustment processingcan be performed in the image forming apparatus which can simultaneouslyreceive calibration instructions in a plurality of modes.

According to a fourth exemplary embodiment, a plurality of options canbe selected from the sheet option buttons 1011 to 1014 on thecalibration sheet setting screen 1010 in FIG. 10D. A case when two of“thick paper” and “thickest paper” are selected as calibration sheets isdescribed below as an example. A grammage of “thickest paper” is definedas “270 g”. Thus, the calibration execution mode using the “thickestpaper” will be a “mode 3” as shown in FIG. 11.

When calibration execution instructions in a plurality of modes aresimultaneously received, the image forming apparatus 101 executescalibration in each mode in turn in a predetermined order. According tothe present exemplary embodiment, calibration is executed in the orderof the mode 2 and the mode 3.

First, the internal adjustment processing when the image formingapparatus having a plurality of image forming modes receives calibrationexecution instructions in a plurality of modes during execution of theinternal adjustment processing is described with reference to theflowcharts in FIGS. 13 and 14. Processing in the present flowchart isrealized by the CPU 104 of the image forming apparatus 101 executing theprocessing according to a program stored in the ROM 105. The processingoverlapping with that in the third exemplary embodiment is not describedin below.

In step S1302 and step S1402, the CPU 104 specifies the calibrationexecution mode as the “mode 2” and the “mode 3”.

Further, in step S1308 and step S1406, the CPU 104 determines whetherthe relevant processing targets on the image forming mode 2 or the imageforming mode 3 with reference to the information table C 1500 of theinternal adjustment processing.

Thus, if execution of calibration using “thick paper” and “thickestpaper” is instructed during execution of the processing A, a reset tableC 1800 shown in FIG. 18 is created. As a result that the determinationprocessing in steps S1306, S1307, and S1308 are each performed on eachof the processing B and subsequent processing, processing which overlapswith calibration and targets on the image forming mode 2 or 3 isexcluded, and processing other than that are set as subsequent executiontargets.

Next, a method for optimizing the internal adjustment processing whenexecution of calibration at startup is reserved in a plurality modes inthe image forming apparatus having a plurality of image forming modes isdescribed with reference to the processing flowchart in FIG. 8.Processing in the present flowchart is realized by the CPU 104 of theimage forming apparatus 101 executing the processing according to aprogram stored in the ROM 105. The processing overlapping with that inthe third exemplary embodiment is not described in below.

In step S802, if it is determined that the calibration is reserved (YESin step S802), the CPU 104 executes the internal adjustment processingaccording to information recorded in an information table E 1900 shownin FIG. 19. According to the present exemplary embodiment, theinformation table E 1900 is recorded in the ROM 105 as many as thenumber of combinations of the calibration execution modes which can bereserved. A case when calibration using “thick paper” and “thickestpaper”, namely calibration in the execution modes 2 and 3 are reservedis described below as an example.

Processing registered in the information table E 1900 is processingindicated as “NO” about overlap with the processing to be performed whencalibration is executed or processing of which target image forming modeis other than “mode 2” or “mode 3” among the processing recorded in theinformation table C 1500. In other words, if calibration in the mode 2or the mode 3 is scheduled to be executed within a predetermined timeperiod after execution of the internal adjustment processing, processingincluded in the internal adjustment processing and in the calibrationprocessing in the mode 2 or the mode 3 is not performed.

As described above, according to the present exemplary embodiment, theoptimization processing is applied to the image forming apparatus havinga plurality of image forming modes and calibration modes in response toa combination of the plurality of calibration modes instructed to beexecuted by a user. Accordingly, even the image forming apparatus whichsimultaneously receives calibration in a plurality of modes can performthe optimization processing by appropriately narrowing down the targetimage forming mode.

Other Embodiments

Embodiments of the present invention can also be realized by a computerof a system or apparatus that reads out and executes computer executableinstructions recorded on a storage medium (e.g., non-transitorycomputer-readable storage medium) to perform the functions of one ormore of the above-described embodiments of the present invention, and bya method performed by the computer of the system or apparatus by, forexample, reading out and executing the computer executable instructionsfrom the storage medium to perform the functions of one or more of theabove-described embodiments. The computer may comprise one or more of acentral processing unit (CPU), micro processing unit (MPU), or othercircuitry, and may include a network of separate computers or separatecomputer processors. The computer executable instructions may beprovided to the computer, for example, from a network or the storagemedium. The storage medium may include, for example, one or more of ahard disk, a random-access memory (RAM), a read only memory (ROM), astorage of distributed computing systems, an optical disk (such as acompact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™),a flash memory device, a memory card, and the like.

While the present invention has been described with reference toexemplary embodiments, it is to be understood that the invention is notlimited to the disclosed exemplary embodiments. The scope of thefollowing claims is to be accorded the broadest interpretation so as toencompass all such modifications and equivalent structures andfunctions.

What is claimed is:
 1. An image forming apparatus, comprising: an imageforming unit; a processor and a memory storing computer code that, whenexecuted by the processor, causes the image forming apparatus to have afirst processing mode and a second processing mode, wherein the firstprocessing mode includes at least a first processing unit and a firstcorrection data generation unit, and the second processing mode includesat least a second correction data generation unit, wherein the firstprocessing unit executes first processing, wherein the first correctiondata generation unit, by using a result of measurement of an imageformed by the image forming unit on an intermediate image transfermember, generates first correction data for correcting a color value ofthe image formed by the image forming unit, wherein generation of thefirst correction data by the first correction data generation unit isone of processing to be performed at time of startup of the imageforming apparatus, and wherein the second correction data generationunit, by using a result of measurement of an image formed by the imageforming unit on paper, generates second correction data for correcting acolor value of the image formed by the image forming unit; and a controlunit configured to: in a case where the first processing mode and thesecond processing mode are executed successively, control execution ofthe first processing unit and skipping execution of the first correctiondata generation unit from among processing in the first processing mode,and successively control execution of the second processing mode, and ina case where the first processing mode and the second processing modeare executed not successively, control execution of the first processingunit and the first correction data generation unit in the firstprocessing mode.
 2. The image forming apparatus according to claim 1,wherein, upon the completion of the startup of the image formingapparatus, either the generation of the second correction data by thesecond correction data generation unit after the generation of the firstcorrection data by the first correction data generation unit or thegeneration of the second correction data by the second correction datageneration unit without the generation of the first correction data bythe first correction data generation unit is selectively executed. 3.The image forming apparatus according to claim 1, wherein the generationof the first correction data by the first correction data generationunit is executed automatically at the time of the startup of the imageprocessing apparatus and predetermined timing.
 4. The image formingapparatus according to claim 3, wherein the predetermined timing is timeand date specified by a user, or timing predicted by the image formingapparatus.
 5. The image forming apparatus according to claim 1, whereinthe image forming apparatus includes a sensor for performing measurementon paper on which a recording material has become fixed over a paperconveying path.
 6. The image forming apparatus according to claim 5,wherein paper on which the image used for generating the secondcorrection data has been formed is measured using the sensor.
 7. Theimage forming apparatus according to claim 1, wherein the control unitis configured to perform control to: after the generation of the secondcorrection data by the second correction data generation unit, executegeneration of the first correction data by the first correction datageneration unit based on a result of the generation of the secondcorrection data.
 8. A method for an image forming apparatus having afirst processing mode and a second processing mode, wherein the firstprocessing mode includes at least first processing and first correctiondata generation and the second processing mode includes at least secondcorrection data generation, the method comprising: execute the firstprocessing; the first correction data generation of, by using a resultof measurement of an image formed by an image forming unit on anintermediate image transfer member, generating first correction data forcorrecting a color value of the image formed by the image forming unit,wherein generation of the first correction data is one of processing tobe performed at time of startup of the image forming apparatus; thesecond correction data generation of, by using a result of measurementof an image formed by the image forming unit on paper, generating secondcorrection data for correcting a color value of the image formed by theimage forming unit; in a case where the first processing mode and thesecond processing mode are executed successively, control execution ofthe first processing and skipping execution of the first correction datageneration from among processing in the first processing mode, andsuccessively control execution of the second processing mode, and in acase where the first processing mode and the second processing mode areexecuted not successively, control execution of the first processing andthe first correction data generation in the first processing mode.
 9. Anon-transitory storage medium storing a program causing a computer toexecute a method for an image forming apparatus having a firstprocessing mode and a second processing mode, wherein the firstprocessing mode includes at least first processing and first correctiondata generation and the second processing mode includes at least secondcorrection data generation, the method comprising: execute the firstprocessing; the first correction data generation of, by using a resultof measurement of an image formed by an image forming unit on anintermediate image transfer member, generating first correction data forcorrecting a color value of the image formed by the image forming unit,wherein generation of the first correction data is one of processing tobe performed at time of startup of the image forming apparatus; thesecond correction data generation of, by using a result of measurementof an image formed by the image forming unit on paper, generating secondcorrection data for correcting a color value of the image formed by theimage forming unit; in a case where the first processing mode and thesecond processing mode are executed successively, control execution ofthe first processing and skipping execution of the first correction datageneration from among processing in the first processing mode, andsuccessively control execution of the second processing mode, and in acase where the first processing mode and the second processing mode areexecuted not successively, control execution of the first processing andthe first correction data generation in the first processing mode.